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US2830970A - Vulcanization of butyl rubber by 2,6-di(acyloxymethyl)-4-hydrocarbyl phenols - Google Patents

Vulcanization of butyl rubber by 2,6-di(acyloxymethyl)-4-hydrocarbyl phenols Download PDF

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Publication number
US2830970A
US2830970A US537047A US53704755A US2830970A US 2830970 A US2830970 A US 2830970A US 537047 A US537047 A US 537047A US 53704755 A US53704755 A US 53704755A US 2830970 A US2830970 A US 2830970A
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parts
aged
tert
butyl rubber
hrs
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Expired - Lifetime
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US537047A
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Inventor
Pliny O Tawney
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Uniroyal Inc
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United States Rubber Co
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Priority to US537047A priority Critical patent/US2830970A/en
Priority to DEU4122A priority patent/DE1163538B/de
Priority to GB29083/56A priority patent/GB800294A/en
Priority to FR1158895D priority patent/FR1158895A/fr
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    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K5/00—Use of organic ingredients
    • C08K5/04—Oxygen-containing compounds
    • C08K5/13—Phenols; Phenolates
    • C08K5/134—Phenols containing ester groups

Definitions

  • This invention relates to a new method of the vulcanization of Butyl rubber by means of (A) certain phenolic compounds in conjunction with (B) heavy metal halides, and also to improved Butyl rubber vulcanizates made with such compounds.
  • Butyl rubber is vulcanized by heating with (A) a 2,6-di(acyloxymethyl)-4-hydrocarbylphenol of the formula (Ina R'COOCHP CHrOOOR' wherein R is a hydrocarbon radical (e. g., an alkyl, aryl, aralkyl or cycloalkyl'radical) and R is an alkyl, chloroalkyl or aryl radical, and R and R preferably each contain 12 carbon atoms or less, and (B) a heavy metal halide.
  • R is a hydrocarbon radical (e. g., an alkyl, aryl, aralkyl or cycloalkyl'radical) and R is an alkyl, chloroalkyl or aryl radical, and R and R preferably each contain 12 carbon atoms or less
  • B a heavy metal halide
  • Butyl rubber, or GR I is a generic name for any of the well knownsynthetic rubbery copolymers of an isoolefin with a minor amountof a conjugateddiolefin.
  • the isoolefins used generally have from 4 to 7 carbon atoms, and such isomonoolefins as isobutylene and 2- methyI-Z-butene are preferred.
  • the diolefins used have from 4 to 8 carbon atoms.
  • Isoprene and butadiene are the most' important of these diolefins; others are piperylene; 2,3-dimethylbutadiene; 3-methyl-l,3-pentadiene; 2- methyl-l'j-pentadiene; 1,3-hexadiene and 2,4-hexadiene.
  • the Butyl rubber typically contains from about 0.5 to and seldom more than 10%, of copolymerized diolefin on the total weight of the elastomer.
  • Typical specific phenolic compounds employed in the invention are 2,6 di(acetoxymethyl) 4-methylphenol;
  • the amount of phenolic compound employed in the invention usually ranges from about 1 part (by weight) to about 12 parts per parts of the Butyl rubber. In general, a preferred range of phenol curing agent is from about 2 parts of 8 parts per 100 parts of the rubber.
  • the heavy metal halide- which may be regarded as a kind of catalyst or activator or curing supplement, since the phenolic material itself will not cure the Butyl rubberis usually used in amount of at least 0.5 parts, and 1 preferably use about 1 to 3 parts, per 100 parts of the Butyl rubber. Although in some cases even larger amounts of the metal halide can be used, say 10 parts, it is not generally necessary or desirable to use appreciably more than about 5 parts. In the majority of cases 1 limit the heavy metal halide to 5 parts or less, and I may even limit it to 1 or 2 parts at times. I customarily use a large amount of the heavy metal halide, e. g., from 5 to 10 parts, when I wish to cure the Butyl very rapidly at a low temperature, e. g., 100 C.
  • the heavy metal halides employed are exemplified by such known stable acidic halides as tin chloride, zinc chloride, iron chloride, and, in general, halides of the various metals usually classified as heavy metals (cf. the periodic chart of the elements in Introductory College Chemistry, by H. G. Deming, published by John Wiley and Sons, Inc).
  • This class includes, inter alia, chromium chloride and nickel chloride, as well as cobalt chloride, manganese chloride and copper chloride.
  • the copper halides may be used, I prefer not to use them because of the possibile deleterious effect of the copper on the Butyl rubber.
  • the heavy metal chlorides constitute the preferred class of activators or vulcanization adjuvants, although the heavy metal salts of other halides including bromine, fluorine, and iodine (such as stannic iodide) may also be used. Of the heavy metal chlorides, the most preferred are those of tin, iron and zinc.
  • the heavy metal halides are effective independently of the state of oxidation of the metal, and they are even effective if the halide is partially hydrolyzed, or is only a partial halide, as in zinc oxychloride.
  • the Butyl rubber, phenolic compound, and heavy metal halide, and any additional desired ingredients may be mixed together in any desired order according to the procedures ordinarily used in mixing rubber compounds, with the aid of the usual rubber mixing equipment, such as an internal mixer or roll mill.
  • the vulcanizable mixture resulting from the foregoing ingredients may be fabricated into the desired form by the usual methods, such as calendaring, extrusion, or molding, and subsequently vulcanized by heating, preferably while confined under pressure.
  • carbon black is present in the products made by the process of this invention.
  • carbon black is present in the products made by the process of this invention.
  • carbon black greatly improves the tensile strength, abra- Second crop, 82 parts, M. P. 9798 C.
  • this invention relates to the cure of gum Butyl rubber and to Butyl rubber which contains other fillers, e. g., clays, titanium dioxide, etc., as well as to black-filled Butyl rubber.
  • the cure is conveniently carried out at temperatures of 100 C. or more, and preferably at temperatures in excess of 150 C., for periods of time ranging from about 5 minutes to 3 hours, the longer periods of time within the stated time range being employed with the lower temperature.
  • the most preferred curing temperatures are within the range of about 160 C. to 190 0., although somewhat higher temperatures may be employed, e. g., 200 to 205 0., provided that such high temperatures are not maintained long enough to cause thermal injury to the article.
  • the time and temperature chosen for a particular cure not only are related inversely to each other but also are dependent on the amount of catalyst used. Therefore, the time and temperature of cure can be given only in the broad ranges shown above. Any skilled rubber compounder can easily determine conventionally the proper curing conditions for any particular stock.
  • the process of this invention is useful in making cured Butyl rubber products which resist aging at high temperatures in steam and/or air extremely well.
  • Typical products are curing bags, steam hose, gaskets for equipment which must remain at high temperatures continuously or intermittently for long periods of time, belts, inner tubes, tires, motor mountings, flexible hot air ducts, hot water bottles, etc.
  • the cured products may also be kept in contact with copper or .silver articles, which would be tarnished by Butyl rubber products cured by, or containing, sulfur.
  • 2,6-di(bromomethyl)-4-tert-butylphenol was first prepared as follows. Glacial acetic acid (630 parts) was saturated with dry hydrogen bromide at room temperature. 2,6-dimethylol-4-tert-butylphenol (210 parts) was added to the stirred solution, to which hydrogen bromide was also added continuously. The mixture was chilled in order to keep its temperature below about 50 C. Within a few minutes the exothermic reaction ended and white needles of the desired product began to form. Hydrogen bromide was shut off. The mixture was stirred at room temperature for a few minutes more in order to complete the crystallization. The 2,6-di-(bromomethyl)- 4-tert-butylphenol was filtered. The filtrate was poured into 500 parts of water to precipitate a second crop of the product. Each crop was recrystallized from petroleum ether. The yield of recrystallized product was:
  • 2,6-di-(chloromethyl)-4-tert-butylphenol (crude product precipitated from AcOH with water and recrystallized from petroleum ether; M. P. 72-74, yield 43%); 2,6-di(bromomethyl)-4-tert,tert-octylphenol (crude product precipitated with Water and recrystallized from petroleum ether; M. P. 93-94", yield 46%); and 2,6- di(bromomethyl)-4-rnethylpheno1 (crude product crystallized from AcOH; M. P. 1145-1155", yield 67%; M. P. after recrystallization from a 40:60 mixture of benzene and petroleum ether, 1190-1195).
  • 2,6-di(bromomethyl)-4-tert-butylphenol (1245 parts) was added to a slurry of 640 parts (5 %excess of theory) of sodium acetate in 3000 parts of glacial acetic acid at room temperature. A white precipitate of sodium bromide formed at once, and the sodium acetate dissolved. The mixture was stirred slowly for 3 hours, and then was poured into 12,000 parts of rapidly stirred water to precipitate 2,6-di(acetoxymethy1)-4-tert-butylphenol. The mixture was neutralized with solid sodium bicarbonate. The said phenol, a pale cream colored product, was filtered and washed well with water. The airdried product weighed 1115 parts, and melted at 61 C. After recrystallization from petroleum ether it melted at 61-62 C., and was white.
  • a stirred mixture of thefirst three materials was heated at 50-55 for 30 minutes to effect the desired reaction.
  • the mixture then was diluted with the benzene and poured into the water.
  • the oily layer was separated and washed successively with water, aqueous sodium bicarbonate and water.
  • the washed solution was dried over sodium sulfate and then was evaporated in vacuo.
  • the residue was extracted withpetroleum ether to remove'impurities.
  • the insoluble portion was recrystallized from cyclohexane to; give 128.5 parts of the desired product.
  • EXAMPLE II A master-batch was mixed on a rubber mill in the proportion of parts of GR-I 15 (a copolymer of isobutylenetisoprene, 98:2, according to Rubber Age, 74, 561- (1954) 50 parts of carbon black, 2 parts of stearic acid and Sparts of Indopol H300 (a commercially available polybutene sold as a plasticizer for rubbers). Sta nnous chloride dihydrate and the phenolic curing agent were then mixed with individual portions of the masterbatch on the mill to form a series of stocks which difiFered among themselves only in the amount of the curing;agent. Portions of these stocks were cured in 6" x 6" x 0.1" molds under pressure at 161 C. (322 F.) for the individual times shown. The stocks then were tested conventionally, as shown, to determine the extentof cure and resistance to aging.
  • GR-I 15 a copolymer of isobutylenetisoprene
  • R is a radical selected from the group consisting of alkyl, aryl, aralkyl and cycloalkyl radicals and R is a radical selected from the group consisting of alkyl, chloroalkyl and aryl radicals, and from 0.5 to 10 parts of a heavy metal halide.
  • a method of vulcanizing a synthetic rubbery copolymer of isobutylene with from 0.5 to of isoprene comprising heating 100 parts by weight of said rubber at a temperature of from 150 C. to 205 C. for from 5 minutes to 3 hours, in admixture with from 2 to 8 parts of 2,6 di(acetoxymethyl) 4-tert,tert.-octylphenol and from 1 to 5 parts of a heavy metal chloride.
  • a method of vulcanizing a synthetic rubbery copolymer of isobutylene with from 0.5 to 10% of isoprene comprising heating 100 parts by Weight of said rubber at a temperature of from 150 C. to 205 C. for from 5 minutes to 3 hours, in admixture with from 2 to 8 parts of 2,6-di(acetoxy-methyl)-4-methylphenol and from 1 to 5 parts of a heavy metal chloride.
  • a method of vulcanizing a synthetic rubbery copolymer of isobutylene with from 0.5 to 10% of isoprene comprising heating parts by weight of said rubber at a temperature of from C. to 205 C. for from 5 minutes to 3 hours, in admixture with from 2 to 8 parts of 2,6-di(benzoxymethyl)-4-tert-butylphenol and from 1 to 5 parts of a heavy metal chloride.
  • An improved vulcanizate characterized by resistance to deterioration at elevated temperatures comprising 100 parts by weight of a synthetic rubbery copolymer of an isoolefin having from 4 to 7 carbon atoms with from 0.5 to 10% of a conjugated diolefin having from 4 to 8 carbon atoms, vulcanized with from 1 to 12 parts of a phenolic compound of the formula R'COOCHs- CHaOCOR' wherein R is a radical selected from the group consisting of alkyl, aryl, aralkyl and cycloalkyl radicals and R is a radical selected from the group consisting of alkyl, chloroalkyl and aryl radicals, and from 0.5 to 100 parts of a heavy metal halide.
  • An improved vulcanizate characterized by resistance to oxidation at elevated temperatures comprising 100 parts by weight of a synthetic rubbery copolymer of isobutylene with from 0.5 to 10% of isoprene, vulcanized with from 2 to 8 parts of 2,6-di(acetoxymethyl)-4-tert-butylphenol and from 1 to 5 parts of a heavy metal chloride.
  • An improved vulcanizate characterized by resistance to oxidation at elevated temperatures comprising 100 parts by weight of a synthetic rubbery copolymer of isobutylene with from 0.5 to 10% of isoprene, vulcanized with from 2 to 9 parts of 2,6-di(acetoxymethyl)-4-tert,tert-octylphenol and from 1 to 5 parts of a heavy metal chloride.
  • An improved vulcanizate characterized by resistance to oxidation at elevated temperatures comprising 100 parts by weight of a synthetic rubbery copolymer of isobutylene with from 0.5 to 10% of isoprene, vulcanized with from 2 to 8 parts of 2,6-di(acetoxymethyl)-4- methylphenol and from 1 to 5 parts of a heavy metal chloride.
  • An improved vulcanizate characterized by resistance to oxidation at elevated temperatures comprising 2,880,970 13 100 parts by weight of a synthetic rubbery copolymer of butylgahenol and from 1 to 5 parts of a heavy metal isobutylene with from 0.5 to 10% of isoprene, vulcanized hlorldc. with from 2 to 8 parts of 2,6-di(propionoxymethyl)-4- tert-butylphenol and from 1 to 5 parts of a heavy metal References Cited in the file of this Patet ChlOIidB. 5 UNITED STATES PATENTS 12.
  • An improved vulcanizate characterized by resist- 2 726 224 Peterson et a1 6 1955 ance to oxidation at elevated temperatures comprising 100 parts by weight of a synthetic rubbery copolymer of iso- OTHER REFERENCES butylene with from 0.5 to 10% of isoprene, vulcanized Van der Mecr: Rubber Chem. Tech., 18, 853--873 with from 2 to 8 parts of 2,6-di(benzoxymethyl)-4-tert- 10 (1945).

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  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Compositions Of Macromolecular Compounds (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
US537047A 1955-09-27 1955-09-27 Vulcanization of butyl rubber by 2,6-di(acyloxymethyl)-4-hydrocarbyl phenols Expired - Lifetime US2830970A (en)

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Application Number Priority Date Filing Date Title
US537047A US2830970A (en) 1955-09-27 1955-09-27 Vulcanization of butyl rubber by 2,6-di(acyloxymethyl)-4-hydrocarbyl phenols
DEU4122A DE1163538B (de) 1955-09-27 1956-09-20 Verfahren zum Herstellen von Vulkanisaten von Butylkautschuk
GB29083/56A GB800294A (en) 1955-09-27 1956-09-24 Improvements in vulcanization of butyl rubber
FR1158895D FR1158895A (fr) 1955-09-27 1956-09-27 Procédé de vulcanisation du caoutchouc butyle

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US537047A US2830970A (en) 1955-09-27 1955-09-27 Vulcanization of butyl rubber by 2,6-di(acyloxymethyl)-4-hydrocarbyl phenols

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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2977348A (en) * 1958-10-07 1961-03-28 Us Rubber Co Vulcanization of butyl rubber with 2, 2'-methylene-bis-(4-nitro-6-acetoxymethylphenol) or 2, 6-bis-(acetoxymethyl)-4-nitrophenol
US3023195A (en) * 1958-05-26 1962-02-27 Exxon Research Engineering Co Preventing scorch in butyl rubber compositions
US3111448A (en) * 1959-02-03 1963-11-19 Us Rubber Co Bonding butyl rubber to nylon
DE1162552B (de) * 1958-09-03 1964-02-06 Albert Ag Chem Werke Verfahren zur Vulkanisation von Natur- und Synthesekautschuk
US3177166A (en) * 1961-01-26 1965-04-06 Goodrich Co B F Antioxidants comprising reaction products of liquid rubbers and phenols and compositions containing same
US3227677A (en) * 1962-01-02 1966-01-04 Phillips Petroleum Co Polyolefins containing bis(hydrocarbyloxycarbonylalkylthioalkyl) phenols as stabilizers
US3321508A (en) * 1962-01-02 1967-05-23 Phillips Petroleum Co Bis-(hydrocarbyloxycarbonylalkylthioalkyl) phenols
WO2004099116A2 (en) * 2003-05-09 2004-11-18 Ciba Specialty Chemicals Holding Inc. Heat sensitive recording material
US20070249957A1 (en) * 2006-04-19 2007-10-25 Patrick Gentempo Mapping spinal muscle tone

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1237302B (de) * 1960-11-29 1967-03-23 Albert Ag Chem Werke Verfahren zum Vulkanisieren von Gemischen aus Butylkautschuk und stark ungesaettigten natuerlichen oder synthetischen Kautschuken
BE638524A (de) * 1962-10-13
FR2532714A1 (fr) * 1982-09-06 1984-03-09 Aerosol Inventions Dev Joints elastomeres pour conditionnement aerosol au dimethylether

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2726224A (en) * 1953-01-02 1955-12-06 Us Rubber Co Acceleration of the reaction between butyl rubber and dimethylol phenols by means of heavy metal halides, and product obtained thereby

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT165035B (de) * 1946-02-01 1950-01-10 Semperit Ag Verfahren zur schwefelfreien Vulkanisation von künstlichem Kautschuk
AT162572B (de) * 1946-02-25 1949-03-10 Semperit Ag Verfahren zur schwefelfreien Vulkanisation von künstlichem Kautschuk
US2649431A (en) * 1951-03-05 1953-08-18 Us Rubber Co Vulcanization of synthetic rubber with alkyl dimethylol phenol and formaldehyde
USRE25007E (en) * 1952-01-12 1961-07-04 Us Rubber Co Vulcanization of butyl rubber with para substituted
GB727953A (en) * 1953-06-29 1955-04-13 Thomas Adam Clayton Improvements in vulcanizing butyl rubber and curing bags made therefrom

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2726224A (en) * 1953-01-02 1955-12-06 Us Rubber Co Acceleration of the reaction between butyl rubber and dimethylol phenols by means of heavy metal halides, and product obtained thereby

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3023195A (en) * 1958-05-26 1962-02-27 Exxon Research Engineering Co Preventing scorch in butyl rubber compositions
DE1162552B (de) * 1958-09-03 1964-02-06 Albert Ag Chem Werke Verfahren zur Vulkanisation von Natur- und Synthesekautschuk
US2977348A (en) * 1958-10-07 1961-03-28 Us Rubber Co Vulcanization of butyl rubber with 2, 2'-methylene-bis-(4-nitro-6-acetoxymethylphenol) or 2, 6-bis-(acetoxymethyl)-4-nitrophenol
US3111448A (en) * 1959-02-03 1963-11-19 Us Rubber Co Bonding butyl rubber to nylon
US3177166A (en) * 1961-01-26 1965-04-06 Goodrich Co B F Antioxidants comprising reaction products of liquid rubbers and phenols and compositions containing same
US3227677A (en) * 1962-01-02 1966-01-04 Phillips Petroleum Co Polyolefins containing bis(hydrocarbyloxycarbonylalkylthioalkyl) phenols as stabilizers
US3321508A (en) * 1962-01-02 1967-05-23 Phillips Petroleum Co Bis-(hydrocarbyloxycarbonylalkylthioalkyl) phenols
WO2004099116A2 (en) * 2003-05-09 2004-11-18 Ciba Specialty Chemicals Holding Inc. Heat sensitive recording material
WO2004099116A3 (en) * 2003-05-09 2005-03-31 Ciba Sc Holding Ag Heat sensitive recording material
US20060240981A1 (en) * 2003-05-09 2006-10-26 Jonathan Campbell Heat sensitive recording material
US7517397B2 (en) 2003-05-09 2009-04-14 Ciba Specialty Chemicals Corp. Heat sensitive recording material
US20070249957A1 (en) * 2006-04-19 2007-10-25 Patrick Gentempo Mapping spinal muscle tone

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DE1163538B (de) 1964-02-20
FR1158895A (fr) 1958-06-20
GB800294A (en) 1958-08-20

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